Separate date and time units in Google Sheets

Start the add-on

1. Select a column that contains those Date time values that you want to split.
   Note. If you select more than one column, only the values from the leftmost column will be processed.
2. Go to Extensions > Power Tools > Start to run the tool:
   
3. Access the Split group:
   
4. And then click the icon representing the add-on:
   

How to separate date and time in Google Sheets

You will see the add-on pane with a few settings to tweak:

1. If the column you selected has a header, check the very first setting. It will keep the top value from being split and will add headers with the corresponding unit names (Date and Time) to new columns.
2. Select those units that you want to get individually in new columns: Date, Time, or both.
   Tip. The unit that you don't choose will be ignored even if it is present in the source column.
3. If the original column is no longer needed, select the last option to replace it with new columns. This way, you won't have to delete the source column manually afterwards.
   Tip. This is especially useful if you want to extract Date/Time units from the Date time record and work with the former only.

Once you're ready, hit Split. You will see the split units in new columns to the right of the original one.